Method of making flexible blanks



Dec. 14, 1943.

A. ELMENDORF METHOD OF MAKING FLEXIBLE BLANKS Filed April '3, 1941Patented Dec. 14, 1943 UNITED STATES PATENT OFFICE METHOD OF MAKINGFLEXIBLE BLANKS Armin Elmendorf, Winnetka, 111.

Application April 3, 1941, Serial No. 386,638

2 Claims.

The common wood barrel must be delivered to most users completely set upand, accordingly, takes up an excessive amount of shipping space inproportion to its weight when empty. Furthermore, the principles onwhich such barrels are constructed cause them to be heavy without beingstrong under rough handling while in a loaded condition. The freightcharges on both empty and full barrels is therefore higher than it iswith respect to lighter, stronger containers of equal capacity of theknocked-down box type. Barrels composed of molded fibrous materials arenot much better than the ordinary wood barrels insofar as the faultsjust noted are concerned.

The present invention has for its object to produce, at a reasonablecost, a barrel composed mainly of wood, which shall be light and yetremarkably sturdy, and which can be shipped in a compact knocked-downcondition and be quickly and easily set up for use.

Thin wood boards or thick wood veneers faced with tough paper are strongand light but, heretofore, it has apparently not been conceived thatsuch materials could be used to make knockeddown barrels or the like.Such two-ply material is stiff and cannot be bent into the shape of acylindrical shell to provide the body for a barrel if it initially beflat. By my invention the twoply structure is permitted either to lieflat or to take the shape of the stiff cylindrical shell required forthe body of the barrel. Therefore, a barrel having such a body membermay be shipped in a knocked-down state and the body member be easilyassembled with suitable heads at the point of use.

The various features of novelty whereby my invention is characterizedwill hereinafter be pointed out with particularity in the claims; but,for a full understanding of my invention and of its objects andadvantages, reference may be had to the following detailed descriptiontaken in connection with the accompanying drawing, wherein:

Figure 1 is a side view of a barrel made in accordance with the presentinvention; Fig. 2 is a top plan view of the barrel; Fig. 3 is a section,on a much larger scale, on line 3-3 of Fig. 1; Fig. 4 is a section, onthe same scale as Fig. 3, on line 4-4 of Fig. 2; Fig. 5 is an edge view,on a still larger scale, of a small fragment of the wood board or veneerafter slitting or grooving; Fig. 6 is a view similar to Fig. 5, showingthe board or veneer bent in the manner required before bonding thefacing sheet thereto, together with the facing sheet in place thereon;Fig. 7 is a view similar to Fig. 6, showing the two-ply panel flattened;Figs. 8 and 9 are views similar to Figs. 5 and 7, respectively, showinga modification; and Figs. 10 and 11 are views similar toFigs, 5 and 6,respectively, showing a still further modification.

In Figs. 1 to 4 of the drawing l represents the cylindrical body of abarrel or keg and 2, 2 represent heads that complete the structure. Thebody member is a panel that is stiff in the direction of the length ofthe cylinder and flexible in the transverse direction to the extent ofbeing able to lie flat or to be curved into cylindrical shape. Insetting up the barrel the meeting edges of the body member areconveniently secured together by a wide tape 3 glued over the jointbetween them, as shown in Figs. 1 and 3. The head members'are of the captype into which the ends of the body member are set. In assembling theparts of a barrel or keg, the bottom head is preferably fastenedpermanently to the body member by spreading glue on the interiorsurfaces of the head or on the periphery of the body member, or both,before placing the head on the body member. After the barrel or keg isfilled, the upper head may be applied and be secured by a tape 4surrounding the barrel and overlapping both the cylindrical wall of thehead and the adjacent portion of the outer surface of the body shell, asshown in Figs. 1 and 4; a suitable bonding material, preferably highlywater resistant, being interposed between the tape and the barrelsurfaces with which it engages. 'The upper head may therefore be easilyreleased by cutting the tape in two lengthwise along the line of thefree edge of the cylindrical wall of the cap. That is, the point of asharp knife need only be pushed through the tape just below the flangeportion of the cap or head in Fig. 4 and be run entirely around thebarrel to cut the head loose.

The body member of the barrel is a fairly thin panel consisting of athin wood board or a piece of thick wood veneer 5 having a much thinnersheet 6 of tough flexible material bonded thereto. In the case of a nailkeg, for example, the wood ply may be about three-sixteenths of an inchI thick and the other ply may be Kraft paper about thirty-thousandths ofan inch thick. Thepaper is preferably waterproofed and the bondingmaterial between the two plies is preferably water resistant. Soya beanadhesive and casein adhesive are suitable for this purpose.

The structure of the body member and the manner of making it areillustrated in Figs. 5 to 7. As appears in Fig. 5, cuts are made throughboth faces of the wood member along parallel lines extending in thegeneral direction of the grain of the wood, as indicated at 'I and 8, soas to transform the wood member into a series of narrow strips connectedtogether by little unsevered sections between the ends of correspondingcuts on opposite faces of said member. In

- the example given, the cuts in each series or group are preferablyspaced about one-half inch apart to produce strips of that width. Thecuts If the facing sheet were glued to the wood with the latter in aflat condition, the resulting panel would be stiff and fiat. However, bycreating the bond between the flexible facing and the panel while thestrips stand at the same angles to each other as they later will in thecompleted barrel,

and forcibly flattening the panel, the panel can.

always be bent into the cylindrical shape when it is desired to do so.As shown in Fig. 6, the size and shape of the slits 8 is such that theseslits are completely closed when the panel takes its cylindrical shape.This not only provides the interior of the barrel body with asubstantially continuous face, but causes each strip to act as a lateralsupport for the two strips between which it lies. The bonding of the twoplies may be accomplished either by progressively bending the wood plyand simultaneously bonding the flexible sheet to the same, or by firstbending the wood ply into its cylindrical shape and then attaching theflexible sheet.

After the bonding has been completed, or as the bonding proceeds if itis done progressively, the panel is flattened as indicated in Fig. '7.It will be seen that the'slits 1 and 8 have now become widened somewhatthrough a stretching of the wood, transversely of the slits and parallelto the faces of thepanel in the regions between the inner ends ofcorresponding slits I and 8; this stretching of the wood ply across thewidth thereof being necessary to compensate for the greatercorresponding dimension of the facing ply which spanned an equal anglebut at the end of a longer radius than the wood ply at the time thebondfiig was effected.

'I'hev slitting or cutting of the wood ply can also be done as indicatedin Figs. 8 and 9. In this construction, the slits 1 of the first formare omitted and the slits l0, corresponding to the slits 8, aredeepened. In the completed, flattened panel, the slits ID are widened asare the slits 8 in Fig. '7 and the transverse .stretching of the woodply occurs in the uncut-sections ll between the bottoms of the slits andthe face to which the sheet 6 is bonded.

In Figs. 10 and 11 the slits l2 and i3 correspond to the slits I and 8as to location, but are in the form of saw cuts or shaper cuts. Thestretching of the wood occurs in the uncut sections between the innerends of corresponding slits or grooves l2 and l3.

All that is needed to produce barrels or kegs of .great strength is toprovide the cylindrical body members with heads that are themselvesstrong and reenforce the ends of the body members. In

-' condition.

the arrangement shown, each head comprises a plywood disk IS the overalldiameter of which equals the outside diameter of the cylindrical shell,while for some distance upward from the under face the diameter isreduced to that of the interior of the shell. Therefore, a part of thedisk flts into an end of the shell while the part of larger diameterrests on the end edge face shell. The cylindrical flange that gives tothe head the character of a cap is part of a multi-ply .heretoforedescribed in detail is the one which I prefer, substantially the sameresults can be obtained by rupturing and expanding the veneer as in myprior patent No. 1,819,775, of August 18, 1931. However, the veneer, inthat case, must be broken down before the flexible facing is appliedthereto, so as to permit the necessary expansion of the veneer to beeffected before bonding the facing sheet thereto. It is, of course,evident that the amount of expansion must be just enough to permit thefractures to close fully on the concave side when the structure assumesthe cylindrical shape.

My novel barrel or keg is very muchstronger and more durable and lastingthan the old types. Thus, for example, a keg of nails embodying thepresent invention resists many times the number of standard drop tests,before showing serious damage, that suffice to destroy an ordinary fullwood nail keg or to break open a full keg composed of molded fibrousmaterial. At the same time, my keg weighs less than the others and canbe shipped in a knocked-down Furthermore, my keg or barrel can be openedquickly by simply cutting the tape that holds on the top head or coverand can be sealed again, after being refilled, by applying a new pieceof tape. Accordingly, goods may be distributed more safely and moresecurely and at a lower cost in my improved containers than in barrelsor kegs or previously known types.

While I have illustrated and described with particularity only thesingle preferred form of my invention, with a few slight modifications,I do not desire to be limited to the exact structural details thusillustrated and described; and intend to cover all forms andarrangements which come within the definitions of my inventionconstituting the appended claims.

I claim:

1. The method of making a flexible blank for a cylindrical containerbody which may be shipped in a flat condition, which consists in cuttinginto at least one face of and partly through a sheet of wood veneeralong parallel lines running in the general direction of the grain totransform it into a series of strips integrally connected with eachother by uncut portions of the veneer, bending the veneer on a radiuscorresponding to that of said body, with said face on the concave side,bonding to the convex side of the veneer a sheet of tough, flexiblematerial, and then flattening the resulting two-ply member.

2. The method of making a flexible blank which may be shipped in a. flatcondition, which consists in cutting into at least one face of andpartly through a sheet of thin wood along parallel lines running in thegeneral direction of the rain to transform it into a series of stripsintegrally connected with each other by uncut portions of the sheet ofwood, bending the sheet of wood into the form of a cylindrical shellwith said face located on the inner side, bonding a sheet of toughflexible material to the exterior of the shell, and then flattening theresulting 5 two-ply member.

ARMIN ELMENDORF.

